SphinxRacing

Earlier this year, I was having an issue with my data files - the AiM would randomly "restart". It would do so - not by starting at the splash screen - but rather like it had a senior moment and continued to capture data. The result was a bunch of chopped up files of the same data session. Is there a way to merge those files into a single file so that I can sync with my video (race render)?

(I was able to fix the underlying problem and haven't had it come up since.)

Matt Romanowski

There is a utility in RS3 to combine sessions.

SphinxRacing

IIRC, you have to do it while connected to the dash unit (MXL2) correct?

Matt Romanowski

No, it's in RS3 for after you have already downloaded. You can merge on download as well.

SphinxRacing

Matt - sorry to be a bother, but the merge feature in RS3 is to merge all sessions, not just to pick a couple. And I don't see how to work it with the laptop not hooked up to the car. Any further guidance you can provide is appreciated.

Matt Romanowski

You can select the files you want to merge when you do the batch convert.



Start with RS3 and selecting batch convert.



You can then choose to merge the sessions and select them individually or by folder.

SphinxRacing

Sorry to bring this thread back from the dead. I've tried to merge two consecutive sessions into one. The reason we have two files is due to a power interruption. This is what I end up with:



So, rather than adding one session at the end of the prior one, I end up with what looks to be superimposed data. Clearly, I couldn't be turning 88mph in 1st gear at 13rpm or have such throttle and brake applications at the same time.

I've tried this with numerous sessions where i have the power interruption anomaly and I get these broken sessions and then I have to manually stitch them together.

BTW, the root cause of the anomaly appears to be a minor voltage drop due to my manually turning on the car's fan. That quick draw causes the dash to reset its laptimer, though the rest of the display keeps going (speed, rpm etc.). It isn't a fresh reboot. So, not sure what to do to manage that voltage drop. This is the MXL2 being used in a spec miata.

ProCoach

Never seen a voltage drop of the supply circuit cause that, unless the logger is connected to the same consumer circuit instead of the master cut-off or post alternator supply Not even in a total-loss system (no alternator).

SphinxRacing

My shop (which has extensive experience with data systems) installed a fuse bar that the aim is wired from. I can literally sit on the grid with the dash running, flick on the fan and watch it reset and then repeat it over and over. I also had a time when I spun off at VIR in Hog Pen. Aim collected data until the car came to a stop (both feet in) and then restarted - car never stalled. I might try a new alternator to address a separate issue and see if that fixes it. (that doesn't solve my data merge issue which is driving me up the wall).

DTMiller

I was having a similar sessions split issue and it was my starting parameters, in slow traffic I was dropping below the start speed/RPM combo.

Although the switch on/off thing is interesting. Any chance it is interfering with the signal upon which the start parameters are based?

Matt Romanowski

What is the serial number of the MXL2?

What are the recording parameters set to in the config?

SphinxRacing

So, I think I figured out the problem with the wonky data. Looks like I can't merge the data and go straight to csv (which I need for race render). I have to merge it as a drk file first and then convert the merged file. And even then, it isn't clean. It does weird stuff during the black flag that's in the middle of the sessions; one time it cut short the time was sitting still by a couple of minutes and the other time it never showed the car stopping at all (got close, but ever actually zero). So, I have to sync the video twice, once for the portion before the black flag and once for the portion after the black flag. So, effectively, I'm not really saving any time/headache by trying to merge the files. I'm generating 2 video files that I then have to stich together.

Also the conversion tool in RS3 to CSV doesn't give me as good a result as the RS2 one. So, using that. So far seems to convert correctly. Is there a way to set the default file for where RS2 should look for the data files?

However, merging the files is still useful for a data comparison across the session.

@Matt - serial is 4302179. Parameters are set to standard "RPM is greater than 850 or speed (not GPS) is greater than 6mph."

DTMiller

Change RPM to 300 and try the switch test. Miata on stock ECU, which I would assume because spec Miata, will have a brief rpm dip with fans coming on and probably just enough to get outside your start parameters. (Which I just learned are also stop parameters if the conditions stop being met.)

Matt Romanowski

You do have a voltage problem. Send me an email matt@trailbrake.com and I can help you with a fix.

SphinxRacing

Matt - quick update. First, thank you for all of your help with resolving this issue. Second, after sending a bunch of files to aim support, they think they found the issue. The trigger RPM to record was set too high. I thought that once triggered, it would record until the car is restarted. Because, IIRC, the setting is for when to start recording, not when to stop. But evidently, if the RPMs fall below that number, even if at 100MPH, then, boom, restart of data collection.

I ran a race a couple of weeks ago and I played around with the fan switch again to see if it would trigger the problem - it didn't. So, running another race this weekend. Hopefully, won't happen again.

Again, thanks for your help. I really do appreciate it.